The present disclosure relates to a technique to estimate the magnitude of the voltage in a power supply line.
Railroad vehicles configured to receive alternating-current power from power supply lines (for example, overhead lines) and to be operated by the alternating-current power are known. This type of railroad vehicle includes a transformer and a power converter. The transformer receives alternating-current primary voltage from a power supply line and converts the primary voltage into secondary voltage and tertiary voltage. The secondary voltage is inputted into the power converter that generates electric power that drives a motor. The tertiary voltage is inputted into a load that is different from the power converter.
Obtaining a voltage value in a power supply line and performing various controls based on the voltage value in a railroad vehicle traveling configured as described above has been considered.
The publication of the Japanese Patent No. 4568111 discloses a power converter configured to detect a voltage value in an alternating-current bus and to control electric power to be supplied to a load based on the voltage value.